The Hollywood writers may still be on strike, but no matter -- TV's not the only game in town anymore.

New research from the Pew Internet and American Life Project identified 2007 as a year of explosive growth for Internet video, with far more Americans tuning in to sites like YouTube to view and share videos online than ever before.

Forty-eight percent of U.S. adult Internet users said that they had been to a video-sharing site, Pew's phone survey found. That's a 45 percent rise over the 33 percent of respondents who said they'd been to such sites at the end of 2006.

Meanwhile, with 15 percent of respondents reporting that they visited a video-sharing site "yesterday," compared with 8 percent the year before, Pew has suggested that average daily traffic has nearly doubled.

Why the spiking interest in online video? In part, Pew attributes the surge to the increasing number of Americans with the high-speed connections needed for a quality viewing experience. In the recent survey, 54 percent of Americans said that they had broadband connections in their home, compared with 45 percent in 2006.

Another factor contributing to the mainstreaming of video-sharing sites is the proliferation of content being made available. Far more amateurs are shooting and posting their own videos on YouTube, and more businesses are opening their eyes to the marketing power of the viral-video phenomenon. YouTube has become a favorite forum for marketers rolling out consumer-generated ad campaigns, which, though their impact on the bottom line is still fuzzy at best, are nonetheless becoming an increasingly popular way to build brand recognition.

Even some big-league content producers, like Universal Music Group, have become prolific YouTube posters.

The ascendancy of YouTube and the video-sharing phenomenon identified in the Pew study is a microcosm of the larger trend of the Internet becoming a legitimate venue for watching video content. In July, Pew reported that 57 percent of adult American Internet users had either downloaded or watched video online. The same percentage reported that they shared links to videos with friends; 75 percent said that they received links from friends.

Parsing the results of the more recent study, Pew found that the popularity of video-sharing sites is still largely driven by men, younger adults and college graduates, who remain among at the top of the YouTube demographics.

While they are still not as interested in online video-sharing as men, women accounted for some of the most dramatic growth in traffic to those sites, Pew found. The portion of women who said they had ever visited a video-sharing site increased 59 percent compared with the previous year.

The portion of woman who reported having visited a video-sharing site "yesterday" in the Pew survey spiked even more sharply, up 120 percent from 2006. The portion of men who said they had visited one of these sites "yesterday" increased 82 percent year-to-year.